Compensating system



June 17, 1930. f L, Y, SPEAR- 1,764,904

COMPENSATING SYSTEM Filed pt. 4, 1928 2 Sheets-Sheet l June 117, 1930. 1.. Y. SPEAR 1,764,90

v COMPENSATING SYSTEM I Filed Sept. 4, 1928 ZShgets-Sheet 2 .Ezwgzzfor lawrene @0607" 'tion, on account Patented June 17, 1930 A ENT j La'wannon YfsrnAn, ornnvr Lennon", oon'nncrronr, "Assrenon'roInLnorRIo'noA'r I COMPANY, or escrow, conn'scrro'c'r, a conronarronorjnnwJEnsnY corsrnnsarme sYs'rEM Application filed September 4, 1928. Serial Ne. 303,814.

This invention relates to means for preserving substantially intact the weight and longitudinal trim of submarine boats.

It is now well known that in order to obtain the required degree ofcontrol in the verticalplane when submerged,the buoyancy and fore and aft trim of a submarine when in diving condition must be kept within certainlimits, which limits vary with the size and details of design. It is also well known that in orcer to be efficient in war, a su marine must be capable of passing very quickly from any surface cruising condition to the diving condition. 7 Since the boat must necessarily carry consumables, such for instance as fuel, lubricating oil, fresh water, provisions, etc., the weight must vary from time to time, and so must also the buoyancy, due to variations in the specific gravity of the water of flotation.

Under these circumstances, it is clear that without compensation the amount of water tovbe taken into the ballast tanks in order 7 to bring the boat into diving condition must be a variable, as, must also the longitudinal gravity of that 7 position of the center of water. This delicate and complicated'operaof the time necessarily consumed, is not consistent with war efficiency and accordingly it is now the universal practice to provide means for compensation whereby the weight and longitudinal trim of theboat in any surface cruising condition are maintained constant within certain limits. The diving condition is then brought more ballast tanks,

This tankcompleteabout by filling one or usually termed main ballast; age 1s, in the submerged condit10n,

. ly full, and its volume thus accurately measures, within the limits above-referred to, the buoyancy which must be maintained by the compensating system in surface cruising condition. "uel is by far the most important consumable for which compensation has to be provided. a V

In order to preserve s'pace,iit' is now common practice to utilize the 'space'v'acated in the fuel tanks by use of fuel for compensat in'g water ballast. In order to avoid mixing the fueland water and foriother good and between the volume of good practice to keep the'fuel tanks when sufficient reasons, it is generally considered in use completely full and'under pressure, Q

the fuel being drawnoif from the top, while an equal volume of Water is admitted to the bottom. j I l When the fuel tank top is below the surface water-line, the admission of water may be directlyrfrom the sea, but when it is above, the required head is obtained by a pump, usually the same pump asis employed forcirculating engine cooling water, since that pump must be in operation when the fuel is being consumed. Now water being heavier than the fuel, it is obvious that the total weight in the fueltank is increased when fuel is consumed and replaced by water, andin order to compensate for this, according to the present practice, the boat starts out with the necessary amount of compensating water carried in other tankage. The amount ,of compensating water required to be so cardetermined by the diiferri'ed is, of course, encebetween the specific gravity of the water of flotation and that of the fuel and the total volume of the fuel tanks. As the fuel is consumed, the weight of the system is kept substantially constant bypassing overs equal in-weight to the difference in weight fuel consumed and the equal volume of flotation water which enters the fuel storage tanks, while the fore andaft trim is maintained.substantially constant by the suitable fore and aft location ofthe compensating water tankage with relation tothe fuel tanks. In practice, this compensating water tankage is for convenience frequently combined with the auxiliary or adjusting tank or tanks. j

The principal obj ection to the vpresent system just described is that it necessarily involves carrying a substantial weight of compensation water, thus increasing thesurface displacement, and decreasing the buoyancy with detrimental effects on seawort'hiness and speed. My 1nvent1on 1S prlmarlly des1gned to avoid the necessity for carrying the com-' pensating waterabove referred to; 1

vFurther objects and advantages of my inboard, an amount of compensating water vention will appear from the detail description.

Fig. 1 is a semi-diagrammatic plan view of a submarine boat of known type showing my'invention as applied thereto;

Fig. 2 is a section taken substantially on line 22 of Fig. 1;

vtively connected Fig. 3 is a semi-diagrammatic plan view of the stern portion of a submarine boat of known type showing afimodified form of my invention as applied thereto.

In general, the essential ballast tanks of any submarine may be divided into'three groups. These are the main ballast tank or tanks designated A which carry the greater part of the water ballast; the fore and aft trimming tanks designated B whose main function is't'he adjustment of longitudinal trim; and the auxiliary or adjusting tank or tanks designated G the center of which is located at or near the center of buoyancy of the boat. when submerged. The volume of water carried when submerged in the main ballast tankage A is constant, whereas that carried in tankage B and C is variable;

The totalfuel tankage isrepresented by the three tanks designated D and E. It should be observed that so long as certain conditionsspecified below are met, the total num v ber of fuel tanks is immaterial, as is also their location in the boat. The volume of tankage E is so proportioned to that of tankage D as to make the total weight, when both are filled with fuel, equivalent to the weight when tankage -D is filled with water of flotation and tankage E is empty.

In addition, this tankage is located and proportioned so as to preserve substantial fixity of the longitudinal center of gravity of the systemas a whole under all conditions. This tankage is provided with the necessary filling and vent connections, with which this invention is not concerned and which are not indicated on the drawings. The boat illustrated is a known type of twin screw submarine provided with engines G of known type. Between the engines and the fuel tank age D-'E are interposed two service and compensating tanks 1 and 1 Tanks 1 and 1 are connected to the engine by a suitable piping system designated generally by 2, which is provided with suitably located valves 3 whereby the tanks can be alternato the engines for supplying fuel thereto. A U-shaped system of piping 4, provided with two valves 5, connects the service tanks 1 and 1 A pipe 6 connects to pipet between valves '5, this pipe-having a valve 7. 1 Branch pipes 8 extend from pipe 6 and open into the top of tanks D. A pipe9, provided with a valve '10 connects to pipe 6 in advance of valve 7 and opens into tank E at the bottom thereof. It will be observed that'with this arrangement either tank 1 or 1 may be employed to serve either one or both engines, while the remaining tank may be completely shut off from the engine supply system and placed in communication with tanks D and E as desired. In addition to the-above, sea valves 11, operated by rods 12 and hand wheels 13, are provided for admitting water of flotation to the bottom of tanks D, and any other suitable means, such as ajpump, may be employed for supplying water to the tanks D.

Obviously without departing from the spirit of the invention, tanks D may be ar ranged to function as one tank by fitting suit able conduit connections at the top and bottom thereof, in which case only a single branch pipe 8 would be required.

Tanks 1 and 1 may be of any desired capacity, but preferably each will be so proportioned as to contain, when full, a weight of fuel not more than the permissible degree of variation in submerged buoyancy. These tanks are provided with the necessary gauges and scales to enable their contents at all times to be accurately determined.

Starting with tankage D and E full of fuel and tanks 1 and 1 empty, the operation is as follows :Tanks 1 and 1 are first filled from tankage E and then shut off from the line 6. One of these tanks, for instance 1, is then placed in communication with one or both engines, while the other, 1 is shut off therefrom; hen 1 is empty, or when any desired amount of fuel has been consumed from it, it is shut off from the engines and 1 is placed in communication therewith. If

- the volume of fuel'consumed from 1 is represented by V, in order to compensate for the weight'expended, a smaller volume of water of flotation must be taken on board, the two volumes in question being in proportion to thespecific gravity of the water of flotation and the fuel. To accomplish this compensation andto again make tank 1 ready for the engine supply service, the following procedure'is adopted :1 is now opened to pipes 6 and 8 andit then receives from tankage D a volume of fuel equal to the volume of compensating water required, which'compensating water is simultaneously admitted to the bottomof tankage D.

The remaining void in tank 1 is then filled with fuel from tankage E, after which tank 1 is shut off from the line and is ready for use again as an engine service tank, as soon as the desired amount of fuel has been consumed from 1. The alternate use of the tanks 1 and 1 as above described serves to always maintain the weight and longitudinal center of gravity of the fuel system within the required limits. The level of the oil in tankage E is being continuously lowered as the level of the water rises in tankage D and when all the fuel has been passed to the service tanks tankage D is filled with the water of flotation, and tankage E is empty. r

. Another embodiment of my invention is represented semi-diagrammatically in Fig.8 where the designations of ballast and fuel storage tanks are identical with those employed in Fig. I. In this second embodiment,

the-arrangement and proportion of tankage nected to the engines as in Fig. 1. Tanks 16,

19 and are equipped with the necessary gauges and scales to enable the contents thereof to be accurately ascertained.

As before, tanks 19 and 20 may be of any desired capacity, but preferably will have a unit capacity for a weight of fuel not greater thanthe maximum permissible variation in submerged buoyancy. While tank 10 may be of any desired capacity, it will normally have a capacity bearing the same relation to the unit capacity of 19 or 20 as the specific gravity of the fuel bears to the specific gravity of the water of flotation.

Starting with tankage D--E full of fuel and tanks 19 and 20 empty, the operation is as follows :-Tanks 1.9 and 20 are first filled with fuel from tankage E and then shut off therefrom, after which eitherone, for instance 19, is opened to the engines, 20 remaining shut off from the engines for the time b8111 When 19 is empty, or any desired amount of oil has been consumed therefrom, it is shut off from the engines and 20 is with. Tank 19 is thenrefilled with fuel from tankage E and an equivalent weight of water is admitted to tank 16 which is thereafter shut off from the water of flotation. The top connections between tankage D and E being open, the water in tank 16 is forced into the bottom of tankage D replacing an equal volume of oil which passes overinto tank E, the effect so far as compensation is concerned beingthe same as in the embodiment of Fig. 1. Obviously and without departing from the spirit of the invention, by making the necessary changes in piping connections the separate compensating tank 16 could be dispensed with and its functions could be performed alternatively by the service tanks 19 and 20. The separate compensating tank 16 is the preferredarrangement, however, since in its absence, carelessness in operation might result in a mixture of fuel and water in the service tanks.

While the foregoing description has purabove described,

' walls, which,

plying water connected thereposely been limited to compensation for fuel only, it is obvious that the same apparatus can also be employed for compensating, for other. consumables, such, for instance, as lubricating oil, freshwater and provisions Vihen the weights of other consumables used bear a fixed and known relation to the weight of fuel consumed in a unit of time or'distance, the result is the same as if a fuel of higher specific gravity were used. In order to maintain constant weight, it is only necessary to take on board a correspondingly increased volume of compensating water. When the system is used for the compensation of other consumables in addition to fuel, that is to say, when the compensating water for such other consumables is eventually lodged in the fuel storage tanks, the stowage for such other consumables must be properly positioned with respect to the tankage D-E in order to preserve fore and trim or other means must be adopted for the regulationof trim independent of'the compensation forv weight. I

It will be observed that with the system tankage D is always full when submerged, and aceordinglyneed not take the pressure of submersion in theouter if desired, can be of light construction provided the inner walls are sufficiently strong to resist the pressure due to' submergence. V r y On the contrary, the contents of tankage E being variable, if this tank is so located as to be exposed to the pressure of submergence, the outer wall must be strong enough to resist that pressure.

lnbotlr forms of my invention illustrated, I employ a suitable pump P and appropriate piping, with suitablyloeated valves, for supto the tanks D when on the s 11'- face'with the upper portionsof these tanks above the water of flotation.

WVhile the drawings illustrate a construction where normally the outer walls ofD would be non-pressure resisting and the outer wall of E would b e pressure resisting,this particular arrangement is by no means essential to the invention. With tankage D arranged as indicated, tankage E might, if desired, be located inside the pressure resist ing hull. Also, tankage D might be located inside the pressure resisting hull, in which case, if of weak construction, it would in the j ubmerged condition be shut off from the waterv of flotation.

VVhatI claim is i 1.111 compensating'means for submarine boats, storage tanks for fuel lighter than but not miscible with water, fuel service tanks, means for supplying fuel to said service tanks from the storage tanks, and means for supplying to the storage tanks water equal in weight to the weight of the fuel withdrawn from said storage tanks.

. of the service'tanks,

2. I11 compensating means for submarine boats, storage tanks for fuel lighter, than but not miscible With Water, means I for Withdrawing fuel from the tanks in unit quantities, and means for supplying to the fuel storage tanks Water equal in Weight to the Weight ofthe unit quantity of, fuel Withdrawn from said tanks.

3. In compensatingmeans for submarine boats, 'storage tanks for fuel lighter than but not miscible with water, means for Withdraw ing fuel from certain of said tanks in unit quantities of volume such that the Weight of a corresponding volume ofwater is Within the permissible variation in buoyancy of the boat, means for supplying to said certain tanks Water equal in volume to the fuel with drawn therefrom, and means for Withdrawing fuel from the remaining fuel tanks.

4. In compensating means for submarine boats,storage tanks for fuel lighter than but not miscible with Water, a pair of service tanks, controlled means for supplying fuel from the storage tanks to either of the service tanks, selectively, means for connecting either of the service tanks, selectively, to the-engines of the boat, andmeans for admitting Water to the storage tanks.

5. Incompensating means for submarine boats, storage tanks for fuel lighter than but not miscible With Water, a pair of service tanks, controlled means for supplying fuel from certain of the storage tanks to either of the service tanks, selectively, controlled means for supplying fuel from the remainder of the storage tanks to the other of the service tanks, selectively, means for alternatively connecting the service tanks to the engines of the boat, and means for admitting Water to said certain storage tanks.

6. In compensating means for submarine boats, storage tanks for fuel lighter than but not miscible With Water, means for withdrawing fuel from the tanks, selectively, and. means for supplying Water to certain of the tanks I in unit quantity, the Weight of such unit quantity being Within and approximately equal to the permissible variation in buoyancy of the boat.

7. In compensatingmeans for submarine boats, storage tanks for fuel lighter than but not miscible with Water, controlled means for WltlldliLWlD tanks, controlled means for Withdrawing fuel from the remainder of'the tanks, and means for supplying Waterto said certain tanks in unit quantity the Weight of which is Within and approximately equal to the permissible variation in buoyancy of the boat.

8. In compensating means for submarine boats, storage tanks for fuel lighter than but not miscible With Water, a pair of service tanks, controlled means for supplying fuel from certain of the storage tanks to either selectively, controlled fuel from certain of said the volume. of. the water measuring tank being such that the Weight of the Water contained therein when full is. Within and ap-. proximately equal to the permissible variation in buoyancy of the boat.

9. The method of compensating for fuel consumed on a submarine boat, consisting in Withdrawing the fuel from certain of the storage tanks/in predetermined unit quantities,

on'ly, the volume of this such that the Weight of a is equal to the Weight of fuel Withdrawn from thestorage tanks at one time, and then replacing the fuel ithdrawn from said certain tanks by anequal volume of Water.

unit quantity being likevolume of Water In Witness Whereor, I hereunto subscribe my name this 8th day of August, 1-928.

LAW'REN Y. SPEAK.

the total amount of]. 

